The discussion below is merely provided for general background information and is not intended to be used as an aid in determining the scope of the claimed subject matter.
Aspects of the invention relate to a rollo assembly, comprising a rotatable winding shaft, a flexible sun screen having forward and rearward ends, wherein the rearward end of the sun screen can be wound on or off the winding shaft and wherein the forward end of the sun screen is provided with an operating beam and wherein the winding shaft is received in a housing that comprises an opening for the passage of the sun screen with a length at least substantially corresponding with a transversal width of the sun screen.
The housing of such a rollo assembly is provided for a number of reasons. For example, it hides the winding shaft (with any mechanism belonging thereto) from sight and it provides constructional means for mounting the winding shaft. An other very important function of the housing is to protect the winding shaft and the sun screen wound thereon against environmental influences, such as impacts (which might cause damage) and dust (which may lead to an unattractive appearance of the assembly, especially the sun screen, and which even may lead to malfunctions of the rollo assembly). With respect to this last function, however, the housing not always is capable of preventing an accumulation of dust on top of the sun screen, especially when applied in an open roof construction of a vehicle with a roof opening closable by a movable panel. Due to aerodynamic effects, in combination with the specific position of the housing in a low pressure zone when the panel is in a position for opening the roof opening, dust will directly and in a concentrated manner settle on the sun screen between the housing and the operating beam (and possibly will enter the housing through the opening). But also dust settling on top of the housing may slide down along the housing towards the sun screen between the housing and sun screen. When the sun screen is maximally wound onto the winding shaft the operating beam may further contribute to this effect. When the sun screen is in a position maximally wound off from the winding shaft, this effect will be far more less because the dust will be distributed over a larger surface and therefore the visual impact will be less.